diff --git a/Makefile b/Makefile
index e72adf2f..f5888027 100644
--- a/Makefile
+++ b/Makefile
@@ -1,121 +1,121 @@
-rwildcard = $(foreach d, $(wildcard $1*), $(filter $(subst *, %, $2), $d) $(call rwildcard, $d/, $2))
-
-ifeq ($(strip $(DEVKITARM)),)
-$(error "Please set DEVKITARM in your environment. export DEVKITARM=<path to>devkitARM")
-endif
-
-include $(DEVKITARM)/base_rules
-
-################################################################################
-
-IPL_LOAD_ADDR := 0x40008000
-LPVERSION_MAJOR := 4
-LPVERSION_MINOR := 2
-LPVERSION_BUGFX := 0
-LPVERSION := \"$(LPVERSION_MAJOR).$(LPVERSION_MINOR).$(LPVERSION_BUGFX)\"
-
-################################################################################
-
-TARGET := TegraExplorer
-BUILDDIR := build
-OUTPUTDIR := output
-SOURCEDIR = source
-BDKDIR := bdk
-BDKINC := -I./$(BDKDIR)
-LOADERDIR := ./loader
-LZ77DIR := ./tools/lz
-BIN2CDIR := ./tools/bin2c
-VPATH = $(dir ./$(SOURCEDIR)/) $(dir $(wildcard ./$(SOURCEDIR)/*/)) $(dir $(wildcard ./$(SOURCEDIR)/*/*/))
-VPATH += $(dir $(wildcard ./$(BDKDIR)/)) $(dir $(wildcard ./$(BDKDIR)/*/)) $(dir $(wildcard ./$(BDKDIR)/*/*/))
-
-OBJS =	$(BUILDDIR)/$(TARGET)/script/builtin.c $(patsubst $(SOURCEDIR)/%.S, $(BUILDDIR)/$(TARGET)/%.o, \
-		$(patsubst $(SOURCEDIR)/%.c, $(BUILDDIR)/$(TARGET)/%.o, \
-		$(call rwildcard, $(SOURCEDIR), *.S *.c)))
-OBJS +=	$(patsubst $(BDKDIR)/%.S, $(BUILDDIR)/$(TARGET)/%.o, \
-		$(patsubst $(BDKDIR)/%.c, $(BUILDDIR)/$(TARGET)/%.o, \
-		$(call rwildcard, $(BDKDIR), *.S *.c)))
-
-GFX_INC   := '"../$(SOURCEDIR)/gfx/gfx.h"'
-FFCFG_INC := '"../$(SOURCEDIR)/libs/fatfs/ffconf.h"'
-
-################################################################################
-
-CUSTOMDEFINES := -DIPL_LOAD_ADDR=$(IPL_LOAD_ADDR)
-CUSTOMDEFINES += -DLP_VER_MJ=$(LPVERSION_MAJOR) -DLP_VER_MN=$(LPVERSION_MINOR) -DLP_VER_BF=$(LPVERSION_BUGFX) -DLP_VER=$(LPVERSION)
-CUSTOMDEFINES += -DGFX_INC=$(GFX_INC) -DFFCFG_INC=$(FFCFG_INC)
-
-# 0: UART_A, 1: UART_B.
-#CUSTOMDEFINES += -DDEBUG_UART_PORT=0
-
-#CUSTOMDEFINES += -DDEBUG
-
-ARCH := -march=armv4t -mtune=arm7tdmi -mthumb -mthumb-interwork
-CFLAGS = $(ARCH) -Os -nostdlib -ffunction-sections -fdata-sections -fomit-frame-pointer -fno-inline -std=gnu11 -Wall -Wno-missing-braces $(CUSTOMDEFINES)
-LDFLAGS = $(ARCH) -nostartfiles -lgcc -Wl,--nmagic,--gc-sections -Xlinker --defsym=IPL_LOAD_ADDR=$(IPL_LOAD_ADDR)
-
-################################################################################
-
-.PHONY: all clean
-
-all: $(OUTPUTDIR)/$(TARGET)_small.bin
-	$(eval BIN_SIZE = $(shell wc -c < $(OUTPUTDIR)/$(TARGET).bin))
-	@echo "Payload size is $(BIN_SIZE)"
-	$(eval COMPR_BIN_SIZE = $(shell wc -c < $(OUTPUTDIR)/$(TARGET)_small.bin))
-	@echo "Compressed Payload size is $(COMPR_BIN_SIZE)"
-
-	@echo "Max size is 126296 Bytes."
-	@if [ ${BIN_SIZE} -gt 126296 ]; then echo "\e[1;33mPayload size exceeds limit!\e[0m"; fi
-	@if [ ${COMPR_BIN_SIZE} -gt 126296 ]; then echo "\e[1;33mCompressed Payload size exceeds limit!\e[0m"; fi
-
-clean:
-	@rm -rf $(BUILDDIR)
-	@rm -rf $(OUTPUTDIR)
-	@rm -rf $(LOADERDIR)/payload_*.h
-
-$(OUTPUTDIR)/$(TARGET)_small.bin: $(OUTPUTDIR)/$(TARGET).bin
-	@$(MAKE) -C $(LZ77DIR)
-	@$(LZ77DIR)/lz77 $(OUTPUTDIR)/$(TARGET).bin
-	@$(MAKE) -C $(BIN2CDIR)
-	@$(BIN2CDIR)/bin2c $(OUTPUTDIR)/$(TARGET).bin.00.lz payload_00 > $(LOADERDIR)/payload_00.h
-	@$(BIN2CDIR)/bin2c $(OUTPUTDIR)/$(TARGET).bin.01.lz payload_01 > $(LOADERDIR)/payload_01.h
-	@rm -rf $(OUTPUTDIR)/$(TARGET).bin.*.lz
-
-	$(MAKE) -C $(LOADERDIR) PAYLOAD_NAME=$(TARGET)_small
-
-$(OUTPUTDIR)/$(TARGET).bin: $(BUILDDIR)/$(TARGET)/$(TARGET).elf
-	@mkdir -p "$(@D)"
-	$(OBJCOPY) -S -O binary $< $@
-
-$(BUILDDIR)/$(TARGET)/$(TARGET).elf: $(OBJS)
-	$(CC) $(LDFLAGS) -T $(SOURCEDIR)/link.ld $^ -o $@
-
-$(BUILDDIR)/$(TARGET)/%.o: $(SOURCEDIR)/%.c
-	@mkdir -p "$(@D)"
-	$(CC) $(CFLAGS) $(BDKINC) -c $< -o $@
-
-$(BUILDDIR)/$(TARGET)/%.o: $(SOURCEDIR)/%.S
-	@mkdir -p "$(@D)"
-	$(CC) $(CFLAGS) -c $< -o $@
-
-$(BUILDDIR)/$(TARGET)/%.o: $(BDKDIR)/%.c
-	@mkdir -p "$(@D)"
-	$(CC) $(CFLAGS) $(BDKINC) -c $< -o $@
-
-$(BUILDDIR)/$(TARGET)/%.o: $(BDKDIR)/%.S
-	@mkdir -p "$(@D)"
-	$(CC) $(CFLAGS) -c $< -o $@
-
-$(BUILDDIR)/$(TARGET)/script/builtin.o: $(BUILDDIR)/$(TARGET)/script/builtin.c
-	@mkdir -p "$(@D)"
-	$(CC) $(CFLAGS) $(BDKINC) -c $< -o $@
-    
-$(BUILDDIR)/$(TARGET)/script/builtin.c: scripts/*.te
-	@mkdir -p "$(@D)"
-	@mkdir -p "$(BUILDDIR)/$(TARGET)/scripts"
-ifeq ($(OS),Windows_NT)
-	@py ts-minifier.py --such-meme -d "$(BUILDDIR)/$(TARGET)/scripts" $(wildcard scripts/*.te)
-	@py te2c.py "$(BUILDDIR)/$(TARGET)/script/builtin" "$(BUILDDIR)/$(TARGET)/scripts"
-else
-	@python3 ts-minifier.py --such-meme -d "$(BUILDDIR)/$(TARGET)/scripts" $(wildcard scripts/*.te)
-	@python3 te2c.py "$(BUILDDIR)/$(TARGET)/script/builtin" "$(BUILDDIR)/$(TARGET)/scripts"
-endif
+rwildcard = $(foreach d, $(wildcard $1*), $(filter $(subst *, %, $2), $d) $(call rwildcard, $d/, $2))
+
+ifeq ($(strip $(DEVKITARM)),)
+$(error "Please set DEVKITARM in your environment. export DEVKITARM=<path to>devkitARM")
+endif
+
+include $(DEVKITARM)/base_rules
+
+################################################################################
+
+IPL_LOAD_ADDR := 0x40008000
+LPVERSION_MAJOR := 4
+LPVERSION_MINOR := 3
+LPVERSION_BUGFX := 0
+LPVERSION := \"$(LPVERSION_MAJOR).$(LPVERSION_MINOR).$(LPVERSION_BUGFX)\"
+
+################################################################################
+
+TARGET := TegraExplorer
+BUILDDIR := build
+OUTPUTDIR := output
+SOURCEDIR = source
+BDKDIR := bdk
+BDKINC := -I./$(BDKDIR)
+LOADERDIR := ./loader
+LZ77DIR := ./tools/lz
+BIN2CDIR := ./tools/bin2c
+VPATH = $(dir ./$(SOURCEDIR)/) $(dir $(wildcard ./$(SOURCEDIR)/*/)) $(dir $(wildcard ./$(SOURCEDIR)/*/*/))
+VPATH += $(dir $(wildcard ./$(BDKDIR)/)) $(dir $(wildcard ./$(BDKDIR)/*/)) $(dir $(wildcard ./$(BDKDIR)/*/*/))
+
+OBJS =	$(BUILDDIR)/$(TARGET)/script/builtin.c $(patsubst $(SOURCEDIR)/%.S, $(BUILDDIR)/$(TARGET)/%.o, \
+		$(patsubst $(SOURCEDIR)/%.c, $(BUILDDIR)/$(TARGET)/%.o, \
+		$(call rwildcard, $(SOURCEDIR), *.S *.c)))
+OBJS +=	$(patsubst $(BDKDIR)/%.S, $(BUILDDIR)/$(TARGET)/%.o, \
+		$(patsubst $(BDKDIR)/%.c, $(BUILDDIR)/$(TARGET)/%.o, \
+		$(call rwildcard, $(BDKDIR), *.S *.c)))
+
+GFX_INC   := '"../$(SOURCEDIR)/gfx/gfx.h"'
+FFCFG_INC := '"../$(SOURCEDIR)/libs/fatfs/ffconf.h"'
+
+################################################################################
+
+CUSTOMDEFINES := -DIPL_LOAD_ADDR=$(IPL_LOAD_ADDR)
+CUSTOMDEFINES += -DLP_VER_MJ=$(LPVERSION_MAJOR) -DLP_VER_MN=$(LPVERSION_MINOR) -DLP_VER_BF=$(LPVERSION_BUGFX) -DLP_VER=$(LPVERSION)
+CUSTOMDEFINES += -DGFX_INC=$(GFX_INC) -DFFCFG_INC=$(FFCFG_INC)
+
+# 0: UART_A, 1: UART_B.
+#CUSTOMDEFINES += -DDEBUG_UART_PORT=0
+
+#CUSTOMDEFINES += -DDEBUG
+
+ARCH := -march=armv4t -mtune=arm7tdmi -mthumb -mthumb-interwork
+CFLAGS = $(ARCH) -Os -nostdlib -ffunction-sections -fdata-sections -fomit-frame-pointer -fno-inline -std=gnu11 -Wall -Wno-missing-braces $(CUSTOMDEFINES)
+LDFLAGS = $(ARCH) -nostartfiles -lgcc -Wl,--nmagic,--gc-sections -Xlinker --defsym=IPL_LOAD_ADDR=$(IPL_LOAD_ADDR)
+
+################################################################################
+
+.PHONY: all clean
+
+all: $(OUTPUTDIR)/$(TARGET)_small.bin
+	$(eval BIN_SIZE = $(shell wc -c < $(OUTPUTDIR)/$(TARGET).bin))
+	@echo "Payload size is $(BIN_SIZE)"
+	$(eval COMPR_BIN_SIZE = $(shell wc -c < $(OUTPUTDIR)/$(TARGET)_small.bin))
+	@echo "Compressed Payload size is $(COMPR_BIN_SIZE)"
+
+	@echo "Max size is 126296 Bytes."
+	@if [ ${BIN_SIZE} -gt 126296 ]; then echo "\e[1;33mPayload size exceeds limit!\e[0m"; fi
+	@if [ ${COMPR_BIN_SIZE} -gt 126296 ]; then echo "\e[1;33mCompressed Payload size exceeds limit!\e[0m"; fi
+
+clean:
+	@rm -rf $(BUILDDIR)
+	@rm -rf $(OUTPUTDIR)
+	@rm -rf $(LOADERDIR)/payload_*.h
+
+$(OUTPUTDIR)/$(TARGET)_small.bin: $(OUTPUTDIR)/$(TARGET).bin
+	@$(MAKE) -C $(LZ77DIR)
+	@$(LZ77DIR)/lz77 $(OUTPUTDIR)/$(TARGET).bin
+	@$(MAKE) -C $(BIN2CDIR)
+	@$(BIN2CDIR)/bin2c $(OUTPUTDIR)/$(TARGET).bin.00.lz payload_00 > $(LOADERDIR)/payload_00.h
+	@$(BIN2CDIR)/bin2c $(OUTPUTDIR)/$(TARGET).bin.01.lz payload_01 > $(LOADERDIR)/payload_01.h
+	@rm -rf $(OUTPUTDIR)/$(TARGET).bin.*.lz
+
+	$(MAKE) -C $(LOADERDIR) PAYLOAD_NAME=$(TARGET)_small
+
+$(OUTPUTDIR)/$(TARGET).bin: $(BUILDDIR)/$(TARGET)/$(TARGET).elf
+	@mkdir -p "$(@D)"
+	$(OBJCOPY) -S -O binary $< $@
+
+$(BUILDDIR)/$(TARGET)/$(TARGET).elf: $(OBJS)
+	$(CC) $(LDFLAGS) -T $(SOURCEDIR)/link.ld $^ -o $@
+
+$(BUILDDIR)/$(TARGET)/%.o: $(SOURCEDIR)/%.c
+	@mkdir -p "$(@D)"
+	$(CC) $(CFLAGS) $(BDKINC) -c $< -o $@
+
+$(BUILDDIR)/$(TARGET)/%.o: $(SOURCEDIR)/%.S
+	@mkdir -p "$(@D)"
+	$(CC) $(CFLAGS) -c $< -o $@
+
+$(BUILDDIR)/$(TARGET)/%.o: $(BDKDIR)/%.c
+	@mkdir -p "$(@D)"
+	$(CC) $(CFLAGS) $(BDKINC) -c $< -o $@
+
+$(BUILDDIR)/$(TARGET)/%.o: $(BDKDIR)/%.S
+	@mkdir -p "$(@D)"
+	$(CC) $(CFLAGS) -c $< -o $@
+
+$(BUILDDIR)/$(TARGET)/script/builtin.o: $(BUILDDIR)/$(TARGET)/script/builtin.c
+	@mkdir -p "$(@D)"
+	$(CC) $(CFLAGS) $(BDKINC) -c $< -o $@
+    
+$(BUILDDIR)/$(TARGET)/script/builtin.c: scripts/*.te
+	@mkdir -p "$(@D)"
+	@mkdir -p "$(BUILDDIR)/$(TARGET)/scripts"
+ifeq ($(OS),Windows_NT)
+	@py ts-minifier.py --such-meme -d "$(BUILDDIR)/$(TARGET)/scripts" $(wildcard scripts/*.te)
+	@py te2c.py "$(BUILDDIR)/$(TARGET)/script/builtin" "$(BUILDDIR)/$(TARGET)/scripts"
+else
+	@python3 ts-minifier.py --such-meme -d "$(BUILDDIR)/$(TARGET)/scripts" $(wildcard scripts/*.te)
+	@python3 te2c.py "$(BUILDDIR)/$(TARGET)/script/builtin" "$(BUILDDIR)/$(TARGET)/scripts"
+endif
diff --git a/bdk/storage/sdmmc.c b/bdk/storage/sdmmc.c
index c87db833..0d305123 100644
--- a/bdk/storage/sdmmc.c
+++ b/bdk/storage/sdmmc.c
@@ -235,10 +235,10 @@ int sdmmc_storage_end(sdmmc_storage_t *storage)
 	return 1;
 }
 
-static int _sdmmc_storage_readwrite(sdmmc_storage_t *storage, u32 sector, u32 num_sectors, void *buf, u32 is_write)
+static int _sdmmc_storage_readwrite(sdmmc_storage_t *storage, u64 sector, u32 num_sectors, void *buf, u32 is_write)
 {
 	u8 *bbuf = (u8 *)buf;
-	u32 sct_off = sector;
+	u64 sct_off = sector;
 	u32 sct_total = num_sectors;
 	bool first_reinit = true;
 
@@ -308,7 +308,7 @@ static int _sdmmc_storage_readwrite(sdmmc_storage_t *storage, u32 sector, u32 nu
 	return 1;
 }
 
-int sdmmc_storage_read(sdmmc_storage_t *storage, u32 sector, u32 num_sectors, void *buf)
+int sdmmc_storage_read(sdmmc_storage_t *storage, u64 sector, u32 num_sectors, void *buf)
 {
 	// Ensure that buffer resides in DRAM and it's DMA aligned.
 	if (((u32)buf >= DRAM_START) && !((u32)buf % 8))
@@ -326,7 +326,7 @@ int sdmmc_storage_read(sdmmc_storage_t *storage, u32 sector, u32 num_sectors, vo
 	return 0;
 }
 
-int sdmmc_storage_write(sdmmc_storage_t *storage, u32 sector, u32 num_sectors, void *buf)
+int sdmmc_storage_write(sdmmc_storage_t *storage, u64 sector, u32 num_sectors, void *buf)
 {
 	// Ensure that buffer resides in DRAM and it's DMA aligned.
 	if (((u32)buf >= DRAM_START) && !((u32)buf % 8))
diff --git a/bdk/storage/sdmmc.h b/bdk/storage/sdmmc.h
index 5dcd10f0..df8fff71 100644
--- a/bdk/storage/sdmmc.h
+++ b/bdk/storage/sdmmc.h
@@ -182,7 +182,7 @@ typedef struct _sdmmc_storage_t
 	sdmmc_t *sdmmc;
 	u32 rca;
 	int has_sector_access;
-	u32 sec_cnt;
+	u64 sec_cnt;
 	int is_low_voltage;
 	u32 partition;
 	int initialized;
@@ -198,8 +198,8 @@ typedef struct _sdmmc_storage_t
 } sdmmc_storage_t;
 
 int  sdmmc_storage_end(sdmmc_storage_t *storage);
-int  sdmmc_storage_read(sdmmc_storage_t *storage, u32 sector, u32 num_sectors, void *buf);
-int  sdmmc_storage_write(sdmmc_storage_t *storage, u32 sector, u32 num_sectors, void *buf);
+int  sdmmc_storage_read(sdmmc_storage_t *storage, u64 sector, u32 num_sectors, void *buf);
+int  sdmmc_storage_write(sdmmc_storage_t *storage, u64 sector, u32 num_sectors, void *buf);
 int  sdmmc_storage_init_mmc(sdmmc_storage_t *storage, sdmmc_t *sdmmc, u32 bus_width, u32 type);
 int  sdmmc_storage_set_mmc_partition(sdmmc_storage_t *storage, u32 partition);
 void sdmmc_storage_init_wait_sd();
diff --git a/source/storage/emummc.c b/source/storage/emummc.c
index 65953ed4..72d93809 100644
--- a/source/storage/emummc.c
+++ b/source/storage/emummc.c
@@ -7,8 +7,8 @@
  *
  * This program is distributed in the hope it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
- * more details.
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
@@ -64,9 +64,9 @@ void emummc_load_cfg()
 					if (!strcmp("enabled", kv->key))
 						emu_cfg.enabled = atoi(kv->val);
 					else if (!strcmp("sector", kv->key))
-						emu_cfg.sector = strtol(kv->val, NULL, 16);
+						emu_cfg.sector = (u32)strtoul(kv->val, NULL, 16);
 					else if (!strcmp("id", kv->key))
-						emu_cfg.id = strtol(kv->val, NULL, 16);
+						emu_cfg.id = (u32)strtoul(kv->val, NULL, 16);
 					else if (!strcmp("path", kv->key))
 						emu_cfg.path = kv->val;
 					else if (!strcmp("nintendo_path", kv->key))
@@ -187,9 +187,17 @@ int emummc_storage_read(sdmmc_storage_t *storage, u32 sector, u32 num_sectors, v
 		return sdmmc_storage_read(storage, sector, num_sectors, buf);
 	else if (emu_cfg.sector)
 	{
-		sector += emu_cfg.sector;
-		sector += emummc_raw_get_part_off(emu_cfg.active_part) * 0x2000;
-		return sdmmc_storage_read(&sd_storage, sector, num_sectors, buf);
+		const u32 part_off   = emummc_raw_get_part_off(emu_cfg.active_part) * 0x2000;
+		const u32 base_sector = emu_cfg.sector + part_off;
+		const u32 abs_sector  = base_sector + sector;
+
+		// Safety: avoid reading past the end of the SD card on very large cards.
+		if ((u64)abs_sector + (u64)num_sectors > (u64)sd_storage.sec_cnt)
+		{
+			EPRINTF("emuMMC read OOR");
+			return 0;
+		}
+		return sdmmc_storage_read(&sd_storage, abs_sector, num_sectors, buf);
 	}
 	else
 	{
@@ -232,9 +240,17 @@ int emummc_storage_write(sdmmc_storage_t *storage, u32 sector, u32 num_sectors,
 		return sdmmc_storage_write(storage, sector, num_sectors, buf);
 	else if (emu_cfg.sector)
 	{
-		sector += emu_cfg.sector;
-		sector += emummc_raw_get_part_off(emu_cfg.active_part) * 0x2000;
-		return sdmmc_storage_write(&sd_storage, sector, num_sectors, buf);
+		const u32 part_off   = emummc_raw_get_part_off(emu_cfg.active_part) * 0x2000;
+		const u32 base_sector = emu_cfg.sector + part_off;
+		const u32 abs_sector  = base_sector + sector;
+
+		// Safety: avoid writing past the end of the SD card.
+		if ((u64)abs_sector + (u64)num_sectors > (u64)sd_storage.sec_cnt)
+		{
+			EPRINTF("emuMMC write OOR");
+			return 0;
+		}
+		return sdmmc_storage_write(&sd_storage, abs_sector, num_sectors, buf);
 	}
 	else
 	{